But Tonight You Belong to Me
by esplanade
Summary: "You. It's always you. John Watson, you keep me right."


A/N: The lovely emillu on tumblr made  
this fanart: post/72999656032/a-missing-scene-from-stag-night-i-always-thought  
and this fanart: post/72485065074/i-cant-even-stand-to-look-at-sherlocks-face-just  
and so naturally I had to write something based on them.  
Because god knows you can never have enough stag night fic.

* * *

"You are bloody ridiculous, you know that?" John could barely get the words out through his laughter as he and Sherlock walked down the street, their steps not quite as steady after all the drinks they'd had. Sherlock had just nearly gotten them into a fight, arguing about ash of all things. John hadn't known quite what to expect when he'd slipped Sherlock the extra shots, but at the very least, the results were entertaining.

"_Ash_, John. He was going to argue about _ash_, with me of all people! As if he knows the first thing about it." Sherlock gave a flip of his hand before shoving both hands into his pockets. He glanced down at John and smiled.

Every shaky step back to Baker Street was laughter and talk and walking so close that their arms brushed against each other's. The pavement was plenty wide; there was no reason to be so close, to be constantly casually bumping into each other. But as if controlled by some new law of physics, Sherlock never seemed to drift more than inches away.

In one of the rare quiet lulls in conversation, John heard Sherlock humming to himself. For a while, John didn't comment, but when it continued, he finally asked, "What are you humming?"

Sherlock didn't answer right away, but did fall silent for a few seconds, a grin at the edge of his lips. He smiled more when he was drunk, John noticed. Or at least, he wore more of those unpracticed, uncontrolled smiles that were always such a rare occurrence on any given day. When Sherlock spoke, he did so with a dismissive little shake of his head. "Just an old song I used to hear when I was a child."

"What song?"

Sherlock's eyes turned toward the sky, as if trying to recall the lyrics. The he stared off straight in front of them, half-singing, half-mumbling some of the words.

"_Way down, way down along the stream, how very, very sweet it will seem once more, just to dream in the silvery moonlight..._" He stopped, laughing a little under his breath. "Child's song."

"Didn't strike me as anything you'd listen to, even as a child."

Sherlock shrugged. "We are all incapable of escaping certain nostalgic aspects of our youths." He paused, on the verge of saying something more, but no words came.

**... ... ...**

_Take my hand. _Such an easy little phrase. He'd said it before. Why couldn't he say it now?

**... ... ...**

Sherlock pulled out his keys, flipping through them and looking at them with intense scrutiny while he tried to find the one for Baker Street's front door. When at last he found it, he attempted to unlock the door, failing miserably, all hand-eye coordination gone. He frowned at the lock. John burst out laughing. "Here, let me, or we'll be out here all night." He reached out, grabbing Sherlock's hand and pulling it away from the door. Sherlock didn't stop him, but he stared blankly at John's hand, eyes half-open. John looked at him for a moment, wondering if he was feeling all right, before slipping the keys out from his fingers. Sherlock seemed to come back to life when the keys left his hand, and he pulled his hand back, balling it into a loose fist before letting it drop to his side.

John met his eyes for a moment, and then easily unlocked the door. Behind him, Sherlock murmured, "Locked room mystery."

"What?" He glanced over his shoulder as he pushed the door open.

"Nothing, nothing." Sherlock followed him into Baker Street, stepping out of the way so John could lock the door. He leaned against the wall at the bottom of the stairs, looking like he was barely able to remain standing. John held out his keys, and Sherlock stared at them in confusion for a second before holding out his hand, palm-up. John almost let them drop into his open palm, but instead placed them there carefully, and folded Sherlock's fingers back over them.

"Don't drop them." Sherlock nodded absently before replacing the keys in his pocket. John grinned. "You don't drink much, do you? You look like you're about to fall over."

"Hmm." Sherlock smiled, staring at the floor between them. "The calculations must have been inaccurate."

"Yeah, sure, the calculations."

"Dizzy."

"What?"

"_Dizzy_." Sherlock pushed himself away from the wall, taking one or two steps and grabbing the edge of the bannister. He sat down on the stairs, leaning against the railing beside him, eyes closed.

After a moment, John sat down next to him. "Lightweight."

"Shut up."

The stairs were narrower than John remembered. When Sherlock sat up straight, they were shoulder to shoulder. Really not wide enough.

There was only one light on, a lamp on a side table across the hall. It created slats of light over them, Sherlock's face shadowed from the light when he turned to look at John.

Perhaps John was more drunk than he had thought.

Sherlock stared at him, glassy-eyed. John thought he saw his eyes glance at his lips, at which point he determined that yes, he was far drunker than he thought. Must be seeing things. Sherlock Holmes wouldn't stare at someone's lips.

A sudden stillness took Sherlock over then, and he leaned back, lying down on the stairs. He sighed. John watched quietly as Sherlock fought to keep his eyes open.

"That can't possibly be comfortable, Sherlock."

"Had worse."

John lay back beside him on his side with his back to the wall. After a while, Sherlock turned to his side as well.

The drinks must have finally hit him. Everything felt so hazy. And it seemed like the stairs had even less room than before.

Sherlock was barely awake, but still periodically he would hum bits and pieces of the same song, the sound fading in and out as he got drowsier.

At one point, he fell asleep entirely. John considered waking him, but he didn't feel much like moving himself. Sherlock shifted in his sleep, one of his legs pressing against John's. When had their faces gotten so close together? John frowned, wondering how the night had become an impressionist blur so quickly. Their faces were mere inches apart. He could almost feel Sherlock's breath on his cheek.

John caught himself running his eyes over every inch of his face, feeling incredibly silly when he did. He turned on to his back, shaking his head. _Drunk and ridiculous._

He stared at the ceiling, hearing Sherlock give one slow, deep breath beside him. Too close, too close and too inviting.

**... ... ...**

"I have an international reputation," Sherlock said softly, his voice thick. "Do _you_ have an international reputation?"

"No, I don't have an international reputation."

"No."

Mrs. Hudson had come out and spoken to them. John missed nearly every word she said. He and Sherlock sat up on the stairs, John's head clearing a bit. Some of the earlier drinks had worn off. Had they been this close to each other all night?

They went upstairs, Sherlock throwing his coat over one of the chairs at the kitchen table rather than hanging it up neatly like he usually did. He was still drunk enough to not care. John reached for the only bottle they had in the flat, grabbing two glasses. He filled them, and handed one to Sherlock, who drank it without question or pause as he walked into the living room.

A small stack of paper on the table caught John's eye. It was sheet music, written in Sherlock's scrawly hand. "What's this? Been composing again?"

"Waltz," he said without facing John. He paced slowly around the living room.

"Why are you writing a waltz?"

"Wedding. First dance."

John paused, his glass halfway to his mouth. "You wrote a waltz for us?"

"For you and Mary."

"That's what I meant."

"Yes." A flick of the wrist, his universal sign for _not important_.

"I don't know how to waltz."

"You don't know how to dance at all. Must learn, though. Every wedding has at least one dance. Silly tradition."

John drained his glass and refilled it. He laughed. "That'll be a train wreck."

"Really, John, it's quite elementary."

"How would you know?"

Sherlock stopped, setting his drink down on the side table by John's chair. He waved him over. John took a few hesitant steps toward him, and Sherlock took the bottle and his glass from his hands and set them down. He reached out and grabbed John's hand, pulling him to the center of the room, positioning his hand on his waist. "You have to learn the man's part." He took John's other hand and held it out to the side. John was too stunned to stop him. "Now whenever you step forward, she'll step back, and vice versa. Look down for now and follow." Sherlock stepped back, and John did as he said, stepping forward with him. "It's very simple, I assure you, even for someone with such limited coordination as yourself." Sherlock walked him through the steps slowly, then faster, occasionally correcting him. "Now, look at me. You can't very well be staring at your feet when you're with Mary." John stumbled a few times, but slowly got the hang of it. He started losing some of the tension in his posture the more comfortable he grew with the motions.

John laughed a little, smiling at Sherlock. "Well thank god now I won't look like a complete moron at least."

Sherlock smiled back, the movements so effortless on his part, even drunk.

"Where did you even learn this?"

"I am a wealth of random knowledge."

"I believe that."

"Yoo-hoo." John stopped when he heard Mrs. Hudson's voice in the doorway. He could feel his face flush.

Mrs. Hudson walked into the kitchen with a tray. "I thought I'd bring you up something before I went to bed. I doubt you got anything like a proper dinner while you were out. Don't let me interrupt."

John cleared his throat and stepped away from Sherlock, letting go of his hand. Sherlock put his hands in his pockets, seemingly unfazed by the landlady's presence.

"Wedding prep," John said.

Mrs. Hudson nodded, a grin on her face, before she left the room. He watched her leave, and could have sworn he heard her stifling laughter.

"Her and Mrs. Turner will have a field day," he said, turning back to Sherlock, who stood a few feet away, just as relaxed and composed as he could possibly be. He gave John a crooked smirk as he crossed the room to finish his drink. He swayed a little where he stood. "How can you teach someone to dance when you're drunk?"

"I managed, didn't I?" He refilled his glass.

John swallowed hard, walking past him into the kitchen under the pretense of seeing what Mrs. Hudson had brought. The reality was that he simply needed a moment to figure out what the hell was going on. He stood at the counter, forcing his breathing to slow down, waiting until he could no longer hear his heart in his ears before turning around.

Sherlock was leaning in the doorway a few feet away, staring into his drink. He was humming the song again as John walked by him into the living room. "Still have that song stuck in your head, do you? How does the rest of it go?" He took a long drink, waiting for Sherlock to say something.

Then he felt an arm around his shoulder, Sherlock coming up beside him, hanging on him, his drink in his free hand. Sherlock reached out to set it down, singing quietly, "_I know_..."

John laughed, his hand on Sherlock's forearm. "Sherlock! Get off!"

Sherlock shifted, leaning against him and resting his head against John's forehead. "_You belong_..."

John's hand slid down to his wrist. "What the hell are you doing?" He grinned, amused. Sherlock's face was just slightly flushed from all the drinks, and so close to John's that he thought he could feel the heat radiate off him.

Sherlock stood in front of him, inches between their faces, resting his hand on John's cheek. He looked at him with a soft expression, eyes half-open again. John stared back at him, his laughter fading as he met the blue eyes.

"..._to somebody new..._"

"Sherlock?"

His voice was hushed, like someone whispering a secret. "_But tonight, you belong to me_." His hand fell to the nape of John's neck. John tried to find the word for the look on his face, and when his brain supplied the word _loving_, it startled him.

But it was so easy for John to close those last few inches between them.

The kiss surprised Sherlock more than it did John, whose hand splayed across his back. But Sherlock wasn't surprised for long before his eyes fell shut, his thumb running gently over John's jaw. When John pulled back, Sherlock stared at him, blinking slowly. After a pause, he tilted John's chin up with his fingers.

"_My honey, I know, with the dawn that you will be gone. But tonight, you belong to me._" Sherlock kissed him, no surprise, no hesitation. But it was John who took the kiss and turned it from something soft and patient to something deeper and far more desperate. Everything was the taste of whiskey and breathlessness and Sherlock's hand on his hip. "_You_. It's always you. John Watson, you keep me right."

"We're drunk," John said.

"Astute observation."

"I probably shouldn't be doing this."

Sherlock paused, looking John in the eye. "And yet here you are."

"You know, we probably won't remember this tomorrow."

"I know."

"I'm getting married."

"I know."

"Then why am I doing this?"

"You tell me." His face was so open, so incredibly unguarded that John swore it was the first time he'd ever actually _seen_ him. It was so obvious to him now. How had he never noticed before? Or had Sherlock just made sure he didn't notice? Had alcohol just stripped away the veneer? Looking at him, at the honesty in those eyes, John was inclined to believe that that was indeed the case.

John didn't tell him. He didn't say anything. He wasn't even sure he knew the answer. All he could do was pull him closer and let the whiskey wash away the night.

**... ... ...**

Sherlock fell asleep with John running his hand through his hair. John lay there in silence for a while, just watching him.

Without waking up – or perhaps without ever having actually fallen asleep, neither would have surprised John – Sherlock reached for John's hand, winding their fingers together between them.

When John could no longer keep his eyes open and finally succumbed to sleep, he wondered if he had been correct in saying they wouldn't remember anything in the morning.

* * *

Sherlock was awake hours before John, his head pounding and cloaked in a terrible brain fog. John was asleep next to him, a fact which at first only drew the reaction of _yes,_ _this is how it should always be_. It took him nearly five minutes to make sense of the situation.

Sherlock sat up in his bed, squinting at the morning light coming in through the window. There were clothes on the floor.

And that was what finally made him understand.

Sherlock carefully got out of bed, doing everything he could to not wake John. He gathered his own clothes and dressed before quietly opening his bedroom door and stepping outside.

He went about his morning as if it were any other morning, after taking some medicine for his headache. But he couldn't focus on anything, cases or experiments. Finally he just resorted to playing his violin as softly as possible. John had long since grown used to sleeping through him playing at strange hours.

A while later, John emerged from his room, dressed, but looking very confused, and almost scared. He pinched the bridge of his nose, a simple gesture to give himself a moment before speaking. Sherlock stopped playing.

John looked up at him, opening his mouth to say something, but no words came. Sherlock knew what he wanted to ask, some variation of _what happened_.

"You were incapable of climbing stairs."

"Sorry?"

"Your old room, upstairs? You were in quite a state."

John winced. "Really?" Sherlock nodded. He'd grown comfortable enough with the lie over the last few hours. "Christ, sorry. Did you get any sleep?"

"Some."

"I stole your room."

"I managed with the sofa. I wasn't asleep for long, anyway."

John shook his head. "I am too old to be drinking enough to not remember the night before." He looked up from the floor at Sherlock. "Do you remember anything?"

Sherlock was quiet for a moment. "Enough."

John laughed. "Well, I hope it was a good night, at least."

"It was."

"Yeah?"

"Yes. Quite a good night."

John seemed relieved. Did he have faint memories of the night before that he had just explained away as a dream in his head? Sherlock hoped so. It was for the best in the long run.

All day though, John would ask Sherlock questions here or there, about what he remembered of the night, Sherlock always giving him predetermined answers. Once, after one such remark, John said, "Are you sure? I could have sworn..." Sherlock waited tensely, watching John try to work through the night. Finally, he conceded, and Sherlock was flooded with relief. There was no reason John should go into a marriage with a guilty conscience.

Once or twice, though, he looked as if he almost hoped Sherlock would confirm whatever nagging visions of the night he had, like he was looking for an out. But Sherlock never did.

Dawn had come, and he belonged to someone else now.

**... ... ...**

Sherlock stood in his room, looking at the fancy clothes and dreading the day.

_For John_, he told himself. _Do it for John_.

_Into battle_.

**... ... ...**

Nothing killed him more than standing there, watching them at the altar, and no words stung more than, "I now pronounce you husband and wife."

**... ... ...**

Sherlock stood in the reception hall, Janine talking to him. He didn't hear most of what she said. He was too busy looking across the room at John and Mary.

_ Look how happy he is. He deserves this. Mary is perfect for him. Nothing I could ever be. Well, not all at once, at least._

_ There is no reason to be so upset over this. It's ridiculous. It could never have been more, even when it seemed like it was. It's selfish of me to even imagine it being just us against the rest of the world. It's a stupid idea anyway. He's Mary's now. He always will be. _

_ He'll have his own family, his own life. He'll forget about me. He'll move on. But he deserves to move on. And if that is what's best for him, I'll let him. Anything for him._

A voice nearby, Janine, asking if he was all right.

He shook himself out of his thoughts and looked down at her. She appeared concerned.

"Yes, fine. Perfectly fine."

**... ... ...**

The speech had the desired effect. People laughed, people cried, people looked at each other with the sentimental gazes that seemed to permeate such affairs.

John had even teared up. And not only that, but had stood and hugged him in the middle of it all. For the first time all day, Sherlock felt like he could breathe. The sensation vanished when John sat back down.

Speeches like these always allowed one to say things that under any other circumstances would draw attention and be the precursor to a serious conversation. People expected sentimentality at a wedding. They expected heartfelt speeches. No one would think anything of it. Including John, who, as always, remained delightfully oblivious to all that _wasn't_ being said, or said only in such a way that it was considered socially acceptable.

Part of him was grateful that everyone seemed to like the speech as much as they did. When he had been writing it, he'd thrown out draft after draft because they all sounded like love letters. Even the final version did, but by then, he didn't know if there was even a way to give a speech without that being the case. He had just hoped that the general public wasn't nearly as perceptive about such things as he was. And he had been right, mostly, although he'd seen Molly look at him sadly at one point, as if she knew. Of course, if anyone knew, who else would it be?

John. John almost always saw what no one else could. But he couldn't see this.

How could he not see?

**... ... ...**

While the reception hall was being converted from dining room to dance floor, Sherlock paced around one of the other rooms in the building. He had done all he could with Janine in regard to her dancing abilities. She wasn't as quick a study as John had been.

He was over the worst of it. All that was left was to play this damn waltz and get the hell out. Everything ached, a horrible feeling in the pit of his stomach.

"Sherlock?"

He stopped, taking a second to wipe the look he was sure he had off his face before he turned around, offering a composed smile to John. "Yes?"

"What are you doing back here?" John looked around at the empty room. "You picked the farthest possible point from everyone else."

"I believe you just answered your own question."

John laughed under his breath. "Well, you have had to be pretty sociable today."

Sherlock clasped his hands behind his back to keep from fidgeting. "I can be, if the situation calls for it."

John stopped a few feet away from him, growing serious all of a sudden. "The speech." He paused, visibly debating what else to say, like he'd expected Sherlock to fill in the blanks for him like he usually did. "It was very good." Sherlock shrugged. "No, seriously. I don't know what I was expecting, but it wasn't that."

"I am a constant surprise."

"Thank you. For everything."

Sherlock couldn't hold the smile on his face any longer. He attempted "neutral," for lack of a better option. He nodded. "It was no problem."

"And all while managing to be mostly inoffensive to everyone. I'm proud." He said it jokingly, although Sherlock believed there was an element of truth to it.

"You keep me right." The words had slipped out before he had a chance to stop them.

"What?"

Sherlock mentally chastised himself, but didn't feel he could backtrack. "It's always you. You keep me right."

Sherlock could almost see John understand. He watched the wheels turn, everything likely flashing before his eyes. His face changed so much so quickly that Sherlock didn't even attempt to keep up with it. All he could do was catalog some of what he saw there: a wave of understanding, dread, panic, and pain.

_Now_ he understood. And Sherlock was too exhausted to debate whether or not that was a bad thing.

"I keep you right."

"Of course."

Had John been standing that close at first? Had he moved and Sherlock hadn't noticed? He certainly seemed awfully close.

Sherlock let his neutrality fall. He didn't have the energy anymore. But he did give John a small, if not bittersweet, smile.

It would have been so easy to cross the room and shut the door on the rest of the world, to try to reclaim some of the quiet privacy they'd had in Baker Street. It could have been easy enough to forget there had just been a wedding, and that there was a bride out there somewhere waiting for her new groom. But it was too late for such things.

When Sherlock actually met John's eyes, he saw it, his own expression, or what he imagined it must have been, mirrored back at him on John's face.

_Oh. That was one more deduction than I was expecting._

How had Sherlock never seen it? John not noticing something would have been common enough, but Sherlock couldn't believe he'd missed something. And _God_, what a thing to miss.

Too little, too late.

"You'd best be getting back to Mary. She'll be waiting for you."

"Jesus Christ, Sherlock." It wasn't the response he'd been expecting. John had more to say, but he failed to say it, and Sherlock let the silence carry on, not knowing how to fill it either.

After a very tense minute, Sherlock waved for John to follow him out of the room.

They walked slowly, weighted down. "Do try to smile, John. It is a wedding reception, after all. I'm told they're supposed to be happy affairs." John was wound up, and no words Sherlock could think of could make it okay. How could he make him see that it was okay?

The hallway at the back of the building had few people in it aside from them, and Sherlock could almost suspend disbelief enough to feel like they were completely alone. He hummed a little as they walked.

"What are you humming?" His voice was tense, all of him still on edge from one too many ill-timed revelations.

"_Although we're apart, you're part of my heart, and tonight, you belong to me_."

John stopped walking, forcing Sherlock to stop as well. You would have thought Sherlock had just told him someone had died. "You asked what I was humming." Sherlock watched as the memories crept back from their alcohol-induced amnesiac prison.

"_Tonight, you belong to me_?"

"Yes. Although I suppose that particular line is no longer accurate. Now come on, you have a waltz waiting for you."


End file.
